1. Field of the Invention
The present invention is related to the field of electronic printers, and more specifically to a computer, a printer and software for changing control settings of a printer's marking device while printing on a page.
2. Description of the Related Art
Electronic printers are used for printing on sheets of paper. A marking device of the printer is set once, for printing on a whole page. This can be a problem in certain situations, especially where different types of printing must be combined on the same page. The problem is exacerbated where a single sheet of paper has regions of different textures, where different settings of the marking device are optimum for printing on each texture. An example is now described.
Referring to FIG. 1, a page 10 has a first region 12 with a first type of texture, and a second region 14 with a second type of texture. The first texture of first region 12 is suited for printing text thereon, while the second texture of second region 14 is suited for printing a photograph thereon. The page 10 can be a special sheet for printing an individual's identification card.
Printers in the prior art define raster scan lines 22, 24 on the entire page 10. Only six such scan lines 22, 24, are shown, but that is only so as not to confuse the drawing. In fact many more are typically defined in a single page. It should be noted that scan lines 24 span only the first region 12, while scan lines 22 span both the first region 12 and the second region 14.
The problem is that the portions of scan lines 22 in the second region 14 appear not sharp, or smudged. That is because a marking device of the printer is set for marking according to what is optimum for the first texture of the first region 12. This setting is typically not also the optimum setting for marking on the second texture of the second region 14.
The problem is simply avoided in the prior art by processing the page 10 through the printer twice. First one prints only on the first region a number of similar pages, and then they eject the page. Then they reinsert the pages in the printer, and reset the marking device for optimum printing on the second region 14. The process is cumbersome, and reinsertion is subject to alignment errors.
The prior art uses a specific data structure (also known as data format) for printer ready data. Referring to FIG. 2, the prior art data structure 200 is described. This is data works with Printer Control Languages (PCLs) and Page Description Languages (PDLs) for printers such as raster printers and other types of printers.
Data structure 200 includes a data group 210 with job settings for marking device initialization. It also includes a data group 210 with job settings for marking device control codes. These are followed by data groups 230, 240, . . . , 250 each of which has raster data for corresponding scan lines. Then follows a data group 260 with job settings for page eject and device reset.
According to data structure 200, the entire page is processed. The marking device moves according to all the raster scan line data, and then the page is ejected. A single setting of the marking device will have to suffice for the entire page.